its a simple-no-picture used art. Firts create a simple radial gradient background, as below..
i have used the black to greenish gradient.
step 2 of 5
Take a thick brush of a bigger size and play around the background.
Do tranform the final image and take copies to have short clouds shapes.
Smudge tool will help you to adjust the edges.
step 3 of 5
draw a shape of a building and fill it uniformly with your color of choice.
I used black as i wanted to create a silhoutte effect.
Make copies of the images and place it separately as u desire.
step 4 of 5
now with the use of pen tool draw a plant like thing
and as usual make several copies to have it placed elsewhere
its jus to Fill up the place and also to create a lively environment
step 5 of 5
the image needs an external/unsual object to show it flying or hanging.
Draw a semicircle and tails to it with the pen tool and reduce the opacity to have it merge to the shape.
now add the ray escaping out of the clouds to create a clean and gloomy atmosphere.
Can also say it a finishing touch, so u get the final image.